Rotary piston machine



July 27, 1965 G. JUNGBLUTH 3,

ROTARY PISTON MACHINE Filed Mdrch z, 1963 lnvenl'or:

a: a7 7317f United States Patent 2 Claims. cl. 230-145 The presentinvention relates to a rotary piston machine, preferably circular pistonmachine, of the general type which comprises an outer confining bodywith lateral confining walls and an inner body or rotor eccentricallyjournalled in said outer confining body and confining therewith theworking chambers of the rotary piston machine. More specifically, thepresent invention relates to a rotary piston machine of the justmentioned type in which between the lateral confining walls for thepiston and the end faces of the piston there are respectively providedlubricant seals which surround the eccentric shaft on which said rotoris journalled.

With heretofore known circular piston machines, the seal of the workingchambers with regard to the journals for the eccentric shaft is effectedby sealing elements which are located on the end faces of the piston andengage said lateral confining walls. The mounting of the sealingelements in or on the piston brings about that the sealing elements aresubjected to centrifugal forces. EX- perience has shown that such anarrangement makes a proper seal difficult. A further drawback of thesaid heretofore known sealing arrangement consists in that lubricant canbe withdrawn only from certain locations in conformity with the rotationof the piston.

It is, therefore, an object of the present invention to provide asealing arrangement for rotary piston machines of the above-mentionedgeneral type, which will overcome the above-outlined drawbacks.

It is another object of this invention to provide a sealing arrangementas set forth in the preceding paragraph, in which the sealing elementswill not be subjected to centrifugal forces.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawing diagrammatically illustrating a verticallongitudinal section through a circular piston machine providedwith anoil seal arrangement according to the present invention.

The oil seal arrangement according to the present invention ischaracterized primarily in that the oil seals are arranged in thelateral confining walls of the outer confining body of the machine. Morespecifically, the lateral confining walls of the outer confining bodyare provided with recess means, for instance an annular groove, forreceiving a sealing ring and the pressing means pertaining thereto.

Referring now to the drawing in detail, the arrangement illustratedtherein shows a piston 1 journalled on an eccentric shaft 2. Piston 1is, in conformity with the general design of well-known rotary pistonmachines, provided with three crests or zenith edges in conformity withthe inner enveloping curve of an epitrochoid. These three ridges, bymeans of sealing strips thereon, seal the working chambers of themachine relative to each other, as is well known in the art, whichworking chambers are formed by the piston and the enveloping bodytherefor, the inner contour of said enveloping body being provided withtwo axis-near zones in conformity with the epitrochoid contour of thepiston. The outer confining body of the rotary piston machine haslateral confining walls or side walls, which are composed of the sidewall members 3 and ring members 7, 7'. The eccentric shaft 2 is3,197,126 Patented July 27, 1965 "ice journalled in the said side walls.For purposes of kinematically controlling piston 1 with regard to theenveloping body, piston 1 is provided with inner teeth 4 in the form ofa gear ring. The inner teeth 4 are in mesh with a pinion 5 of a pair ofpinions the other pinion 5a of which meshes with teeth of a ring gear 6forming part of a stationary ring 7. Ring 7 is connected to the adjacentside Wall members 3 by means of screws 8. The outer peripheral surfaceof ring 7 is adjacent bore 9 of the adjacent side wall member 3 providedwith an annular cutout 7a in which is mounted a sealing ring 10sealingly engaging the adjacent end face of piston 1. Similarly, ring 7is provided with an annular cutout 7a having arranged therein a sealingring 10 engaging the adjacent end face of piston 2. Behind the sealingrings 10, 10' there are respectively provided springs 11 whichcontinuously urge the sealing rings 10,19 against piston 1 whileexerting upon said sealing rings the necessary sealing pressure.

As will be evident from the above, with an arrangement of the lubricantseals according to the invention, the sealing elements are not subjectedto centrifugal forces. The function of the sealing elements is,therefore, easier to control. Inasmuch as the sealing elements have acertain position with regard to the lateral confining Walls of themachine, the sealing will be greatly facilitated. It is easy to providea continuous oil return at the inner circumference of the seal.

With a circular piston machine operating as internal combustion engine,the sealing elements arranged in the lateral confining walls of themachine are better protected against heat emanating from the combustionchamher than is the case with heretofore known circular piston engines.

With the arrangement of the sealing elements in conformity with thepresent invention, it is, therefore, possible when employing rubberelements on the sealing system, to use less heat resistant and thereforecheaper rubber elements.

As will also be evident from the above, with a rotary piston machine inwhich the lateral confining walls of the machine have bores withbushings therein, it is possible advantageously to provide the bushingswith annular recesses or the like for receiving the sealing means. Oneor both bushings may at the same time be provided with stationary gearmeans necessary for the kinematic control of the piston relative to theconfining body of the machine. In particular, rings or the like forholding the sealing elements, are avoided by the present invention.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular construction shown in the drawing, butalso comprises any modifications within the scope of the appendedclaims. Thus, while the drawing shows the gear system 4,.5, 5a, 6 on oneside only of piston 1, it may, of course, be duplicated for the otherside of the piston, in which instance ring 7 could be replaced by a ringsimilar to ring 7.

It is furthermore to be understood that the invention is applicable torotary piston engines of all types, which means for rotary pistonengines which operate as internal combustion engine, as blower, or aspump. This applies to rotary piston machines as well as to circularpiston machines.

What I claim is:

1. A rotary piston machine, especially circular piston machine, whichcomprises: a stationary outer confining body including two lateralconfining wall means, eccentric shaft means rotatably journalled in saidouter confining body, a rotary piston arranged within said confiningbody and journalled on said eccentric shaft means, said rotary pistonhaving its axis of rotation substantially perpendicular to said lateralconfining wall means, each of said lateral confining wall meanscomprising a Wall member with a bore having its axis extending in thedirection of the axis of rotation of said eccentric shaft means, tworing means respectively extending into said bores and connected to saidwall members, each of said wall members confiningwith the ring meansconnected thereto an annular chamber extending in spaced relationshiparound the axis of said rotary piston and opening toward the respectiveadjacent end face of said piston, sealing means respectively mountedwithin said annular chamber for sealing engagement with the end faces ofsaid rotary piston, and means located in said annular chambers andyieldably pressing said sealing means against the respective adjacentend faces of said piston.

2. A rotary piston machine, especially circular piston machine,according to claim 1, in which at least one of References Cited by theExaminer UNITED STATES PATENTS,

647,717 4/1900 Dearing. 892,351 6/08 Beaubien. 3,033,180 5/62 Bentele1238 FOREIGN PATENTS 647,7 ()9 8/62 Canada.

LAURENCE V.- EFNER, Primary Examiner.

1. A ROTARY PISTON MACHINE, ESPECIALLY CIRCULAR PISTON MACHINE, WHICHCOMPRISES: A STATIONARY OUTER CONFINING BODY INCLUDING TWO LATERALCONFININF WALL MEANS, ECCENTRIC SHAFT MEANS ROTATABLY JOURNALLED IN SAIDOUTER CONFINING BODY, A ROTARY PISTON ARRANGED WITHIN SAID CONFININGBODY AND JOURNALLED ON SAID ARRANGED WITHIN SAID CONFINING BODY PISTONHAVING ITS AXIS OF ROTATION SUBSTANTIALLY PERPENDICULAR TO SAID LATERALCONFINING WALL MEANS, EACH OF SAID LATERAL CONFINING WALL MEANSCOMPRISING A WALL MEMBER WITH A BORE HAVING ITS AXIS EXTENDING IN THEDIRECTION OF THE AXIS OF ROTATION OF SAID ECCENTRIC SHAFT MEANS, TWORING MEANS RESPECTIVELY EXTENDING INTO SAID BORES AND CONNECTED TO SAIDWALL MEMBERS, EACH OF SAID WALL MEMBERS CONFINING WITH THE RING MEANSCONNECTED THERETO AN ANNULAR CHAMBER EXTENDING IN SPACED RELATIONSHIPAROUND THE AXIS OF SAID ROTARY PISTON AND OPENING TOWARD THE RESPECTIVEADJACENT END FACE OF SAID PISTON, SEALING MEANS RESPECTIVELY MOUNTEDWITHIN SAID ANNULAR CHAMBER FOR